Linear compressor

ABSTRACT

A linear compressor including a casing, a driving unit provided within the casing, a compressing unit driven by the driving unit, compressing refrigerant, and a supporting spring elastically supporting the compressing unit, a projection projecting from on one of the compressing unit and a ceiling part of the casing, and a stopper provided in a remaining one thereof, movably accommodating the projection within a predetermined movable range. With this configuration, the linear compressor is capable of preventing a collision between a compressing unit and an inner face of a casing.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of Korean Patent ApplicationNo. 2002-66098, filed Oct. 29, 2002, in the Korean Intellectual PropertyOffice, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a linear compressor, and moreparticularly, to a linear compressor to prevent collision between acompressing unit and an inner face of a casing, thereby improvingreliability and a stability of the linear compressor.

[0004] 2. Description of the Related Art

[0005] Referring to FIG. 4, a conventional linear compressor comprisesan outer casing 105 which is closed, and a compressing unit 111 drivenby a driving unit 131 to draw in, to compress and to dischargerefrigerant within the outer casing 105.

[0006] The compressing unit 111 comprises a cylinder block 115supporting a bottom of an outer core 137 of the driving unit 131 andforming a compressing chamber 113, a piston 121 installed to reciprocatewithin the compressing unit 113 and a cylinder head 123 provided on abottom of the cylinder block 115 and having a valve part (not shown)formed with a suction valve (not shown) to draw in the refrigerant and adischarge valve (not shown) to discharge the refrigerant.

[0007] The driving unit 131 comprises an inner core 133 provided outsidethe cylinder block 115, an outer core 137 having a coil 135 wound in anannular manner, in an inside thereof and separated from acircumferential surface of the inner core 133 with a predeterminedinterval, a magnet 141 provided between the inner core 133 and the outercore 137, having a reciprocating motion through an electromagneticinteraction with magnetic fields from the inner core 133 and the outercore 137, and an inner core supporting unit 134, installed on thecylinder block 115 between the inner core 133 and the cylinder block115, to support the inner core 133.

[0008] A stationary frame 145 and the cylinder block 115 supporting theouter core 137 are, respectively, mounted on a top and a bottom of theouter core 137.

[0009] A plurality of steel plates comprising the outer core 137 arestacked and the stacked steel plates engage with the stationary frame145 and the cylinder block 115 by a plurality of bolts 143 to engage theouter core 137 and displaced remote from a circumferential face of theouter core 137 by a predetermined interval.

[0010] On a top of the piston 121 of the compressing unit 111 is mounteda movable unit 151, a portion of which supports the magnet 141 in astationary manner, the magnet 141 being provided between the inner core133 and the outer core 137 of the driving unit 131. The movable unit 151is linked with a vertical reciprocating motion of the magnet 141,thereby allowing the piston 121 to vertically reciprocate within thecompressing chamber 113.

[0011] Over the movable unit 151 and the stationary frame 145 is mounteda vibrating spring 153 to double a vertical reciprocating motion of thepiston 121.

[0012] In this type of a conventional linear compressor, a lower part ofthe compressing unit 111 is supported by the outer casing 105 bysupporting springs 108 disposed between a lower part of the cylinderblock 115 and an inner bottom of the outer casing 105. However, becausean upper part of the compressing unit 111 is free to move, a part of thecompressing unit 111, that is, the stationary frame 145 or the vibratingspring 153, is collidable with an inside wall of the outer casing 105while the linear compressor is in operation, and due to the collision,the reliability and the stability of the linear compressor is lowered.

[0013] Further, the problem may be caused in a course of manufacture ora delivery of the conventional linear compressor.

SUMMARY OF THE INVENTION

[0014] Accordingly, it is an aspect of the present invention to providea linear compressor to prevent a collision between a compressing unitand an inner face of a casing, thereby improving reliability and astability of the linear compressor.

[0015] Additional aspects and/or advantages of the invention will be setforth in part in the description which follows and, in part, will beobvious form the description, or may be learned by practice of theinvention.

[0016] The above and/or other aspects are achieved by providing a linearcompressor comprising a casing, a driving unit provided within thecasing, a compressing unit driven by the driving unit, compressingrefrigerant, and a supporting spring elastically supporting thecompressing unit, a projection projected on one of the compressing unitand a ceiling part of the casing, and a stopper provided in a remainingone thereof, movably accommodating the projection within a predeterminedmovable range.

[0017] According to an aspect, the compressing unit includes a cylinderblock provided within the casing, forming a compressing chamber, apiston installed to reciprocate within the compressing chamber, amovable unit connected to the piston, reciprocating together with thepiston, and a vibrating spring disposed over the movable unit,increasing the reciprocating motion of the piston and the movable unit.

[0018] According to an aspect, the linear compressor further comprises asupporting member combined with a top of the vibrating member, whereinthe projection is projected upward toward the inner ceiling part of thecasing from a top of the supporting member and the stopper is providedin the inner ceiling part of the casing to accommodate the projection.

[0019] According to an aspect, the linear compressor comprises asupporting member combined with the top of the vibrating member, whereinthe projection projects downward toward the supporting member from theinner ceiling part of the casing and the stopper is provided on the topof the supporting member to accommodate the projection.

[0020] According to an aspect, the supporting member comprises acombining part combined with the top of the vibrating member, radiallyextending downward from a center of the supporting member.

[0021] According to an aspect, an opening is formed in the projectionalong a vertical direction.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] These and/or other aspects and advantages of the presentinvention will become apparent and more readily appreciated from thefollowing description of the embodiments, taken in conjunction with theaccompany drawings of which:

[0023]FIG. 1 is a longitudinal sectional view of a linear compressoraccording to a first embodiment of the present invention;

[0024]FIG. 2 is a sectional view taken along line II-II of FIG. 1;

[0025]FIG. 3 a longitudinal sectional view of a linear compressoraccording to a second embodiment of the present invention; and

[0026]FIG. 4 is a longitudinal sectional view of a conventional linearcompressor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Reference will now be made in detail to the embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to like elementsthroughout. The embodiments are described below in order to explain thepresent invention by referring to the figures.

[0028]FIG. 1 is a longitudinal sectional view of a linear compressoraccording to a first embodiment of the present invention, and FIG. 2 isa sectional view taken along line II-II of FIG. 1. Referring to FIGS. 1and 2, the linear compressor comprises an outer casing 5 which isclosed, and a compressing unit 11 driven by a driving unit 31, drawingin, compressing and discharging refrigerant within the outer casing 5.

[0029] The compressing unit 11 includes a cylinder block 15 supporting abottom of an outer core 37 of the driving unit 31 and forming acompressing chamber 13, a piston 21 installed so as to be able toreciprocate within the compressing chamber 13, and a cylinder head 23having a valve part provided below the cylinder block 15, the valve partbeing formed with a suction valve (not shown) drawing in the refrigerantand a discharge valve (not shown) discharging the refrigerant.

[0030] The driving unit 31 comprises an inner core 33 provided outsidethe cylinder block 15, an outer core 37 having a coil 35 wound in anannular manner, in an inside thereof and separated from acircumferential surface of the inner core 33 with a predeterminedinterval, a magnet 41 provided between the inner core 33 and the outercore 37, having a reciprocating motion through an electromagneticinteraction with magnetic fields from the inner core 33 and the outercore 37, and an inner core supporting unit 34, installed on the cylinderblock 15 between the inner core 33 and the cylinder block 15, to supportthe inner core 33.

[0031] A stationary frame 45 and the cylinder block 15 supporting theouter core 37 are, respectively, mounted on a top and a bottom of theouter core 37. A lower part of the compressing unit 11 is supported bythe outer casing 5 by supporting springs 8 disposed between a lower partof the cylinder block 15 and an inner bottom of the outer casing 5.

[0032] A plurality of steel plates comprising the outer core 37 arestacked and the stacked steel plates engage with the stationary frame 45and the cylinder block 15 by a plurality of bolts 43 to engage the outercore 37 and displaced remote from a circumferential face of the outercore 37, by a predetermined interval.

[0033] On a top of the piston 21 of the compressing unit 11 is mounted amovable unit 51, a portion of which supports the magnet 41 in astationary manner, the magnet 41 being provided between the inner core33 and the outer core 37 of the driving unit 31 while maintaining thepredetermined interval. The movable unit 51 is linked with a verticalreciprocating motion of the magnet 41, thereby allowing the piston 21 tovertically reciprocate within the compressing chamber 13.

[0034] Over the movable unit 51 and the stationary frame 45 is mounted aplurality of vibrating springs 53 to double a vertical reciprocatingmotion of the piston 21, the vibrating springs 53 being stacked by bolts57. Between the vibrating springs 53 are disposed spring spacers (notshown). The vibrating spring 53 and a top of the movable unit 51 arecombined by a stationary shaft 59.

[0035] Between the vibrating springs 53 and an inner ceiling part on ofthe outer casing 5 is provided a supporting unit supporting thecompressing unit 11 so as to prevent a collision between the compressingunit 11 and an inner wall of the outer casing 5.

[0036] The supporting unit comprises a supporting member 60 combinedwith a top of the vibrating springs 53, being formed with a projection61, and a stopper 70 provided on the inner ceiling part of the outercasing 5, accommodating the projection 61 of the supporting member 60.

[0037] The supporting member 60 comprises the projection 61 and aplurality of (e.g., three) combining parts 63, the projection 61projecting toward the inner ceiling part of the outer casing 5 from amiddle top thereof and the combining part 63 radially extending aroundthe projection 61, combining with the top of the vibrating springs 53 bya bolt 64.

[0038] The projection 61 is formed with an opening 62 produced bypenetrating the projection 61 vertically. The stationary shaft 59 passesthrough the opening 62 when engaging the movable unit 51 and thevibrating springs 53 to facilitate an engagement operation.

[0039] The stopper 70 accommodating the projection 61 is positioned inthe inner ceiling part of the outer casing 5 opposite to the projection61. The stopper 70 may accommodate the projection 61, allowing theprojection 61 to move within a predetermined range (indicated “a” inFIG. 1) since the bottom of the stopper 70 is opened downward so as tosufficiently accommodate the projection 61.

[0040] With this configuration, if power is applied to the coil 35annually wound inside the outer core 37, magnetic flux originated fromthe application interacts with a magnetic field from the magnet 41connected to the movable unit 51, to thereby reciprocate the piston 21in a vertical manner. If the piston 21 reciprocates vertically, therefrigerant flowing into the compressing chamber 13 is compressed andthen discharged into the discharge valve of the valve part. Acompression and discharge process will be repeated, successively, untila capacity of cooling as needed is achieved. A larger driving forceresulting from the vibration is acquirable by making a mass of thepiston 21 and a number of proper vibration of the vibrating springs 53have a value almost correspond to a frequency of power supplied.

[0041] The linear compressor is able to prevent damage due to acollision between the stationary frame 45 or the vibrating springs 53 ofthe compressing unit 11 and the inner wall of the outer casing 5 sincethe projection 61 of the supporting member 60 combined with thevibrating springs 53 is movably accommodated within the stopper 70provided in the inner ceiling part of the outer casing 5, and a rangethat the top of the compressing unit is movable is limited to thepredetermined movable range “a” due to a combination of the stopper 70and the projection 61.

[0042] According to the above-described first embodiment of the presentinvention, a projection 61 is formed in the supporting member 60 and thestopper 70 is formed in the inner ceiling part of the outer casing 5,opposite to the projection 61, and the projection 61 of the supportingmember 60 is movably accommodated in the stopper 70 on the inner ceilingpart of the outer casing 5. However, according to the second embodimentshown in FIG. 3, since a projection 80, projecting downward toward asupporting member 90, is formed in the inner ceiling part of the outercasing 5 and a stopper 91 accommodating the projection 80 is formed on atop of the supporting member 90, the projection 80 on the inner ceilingpart of the outer casing 5 may limitedly move within the stopper 91 apredetermined amount.

[0043] As is described above, a linear compressor capable of preventinga collision between a compressing unit and an inner face of a casing isprovided, thereby improving reliability and a stability of a product.

[0044] Although a few embodiments of the present invention have beenshown and described, it will be appreciated by those skilled in the artthat changes may be made in these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined inthe appended claims and their equivalents.

What is claimed is:
 1. A linear compressor comprising a casing; a driving unit provided within the casing; a compressing unit driven by the driving unit, compressing refrigerant; a supporting spring elastically supporting the compressing unit; a projection projecting from one of the compressing unit and a ceiling part of the casing; and a stopper provided in a remaining one thereof, movably accommodating the projection within a predetermined movable range.
 2. The linear compressor according to claim 1, wherein the compressing unit comprises: a cylinder block provided within the casing, forming a compressing chamber; a piston installed to reciprocate within the compressing chamber; a movable unit connected to the piston, reciprocating together with the piston; and a vibrating member disposed over the movable unit, increasing a reciprocating motion of the piston and the movable unit.
 3. The linear compressor according to claim 2, further comprising: a supporting member combined with a top of the vibrating member, wherein the projection projects toward an inner ceiling part of the casing from a top of the supporting member and the stopper is provided in the inner ceiling part of the casing to accommodate the projection.
 4. The linear compressor according to claim 2, further comprising: a supporting member combined with a top of the vibrating member, wherein the projection projects toward the supporting member from an inner ceiling part of the casing and the stopper is provided on a top of the supporting member to accommodate the projection.
 5. The linear compressor according to claim 3, wherein the supporting member comprises: a combining part combined with the top of the vibrating member, radially extending downward from a center of the supporting member.
 6. The linear compressor according to claim 4, wherein the supporting member comprises: a combining part combined with the top of the vibrating member, radially extending downward from a center of the supporting member.
 7. The linear compressor according to claim 5, wherein the projection comprises: an opening formed therein along a vertical direction.
 8. The linear compressor according to claim 6, wherein the projection comprises: an opening formed therein along a vertical direction.
 9. The linear compressor according to claim 1, wherein the projection and the stopper have a common shape.
 10. The linear compressor according to claim 9, wherein the projection and the stopper have a cylindrical shape.
 11. A linear compressor having a casing with a compressing unit disposed therein to compress refrigerant, and a supporting spring elastically supporting the compressing unit, comprising: a projection; and a stopper, the projection and the stopper having corresponding structures, each of the projection and stopper being attached to a respective one of the compressing unit and a ceiling part of the casing such that the compressing unit is prevent from moving outside of a predetermined movable range.
 12. A linear compressor having a casing with a compressing unit disposed therein to compress refrigerant, and a supporting spring elastically supporting the compressing unit, comprising: a collision prevention unit to prevent a collision between the compressing unit and an inner wall of the casing by limiting a movement of the compressing unit from moving outside of a predetermined movable range toward an inner wall of the casing.
 13. A linear compressor, comprising: a casing; a compressing unit disposed within the casing to compress refrigerant; a supporting spring moveably supporting the compressing unit; a projection projecting from one of the compressing unit and a ceiling part of the casing; and a stopper provided in a remaining one of the compressing unit and a ceiling part of the casing to movably accommodate the projection within a predetermined movable range.
 14. The linear compressor according to claim 13, wherein the compressing unit comprises: a cylinder block to form a compressing chamber; a piston installed to reciprocate within the compressing chamber; and a movable unit connected to the piston to reciprocate together with the piston.
 15. The linear compressor according to claim 14, further comprising: a vibrating member disposed adjacent to the movable unit to increase a reciprocating motion of the piston and the movable unit; and a supporting member combined with a top of the vibrating member, wherein the projection projects toward an inner ceiling part of the casing from a top of the supporting member and the stopper is provided at the inner ceiling part of the casing to accommodate the projection.
 16. The linear compressor according to claim 14, further comprising: a vibrating member disposed adjacent to the movable unit to increase a reciprocating motion of the piston and the movable unit; and a supporting member combined with a top of the vibrating member, wherein the projection projects toward the supporting member from an inner ceiling part of the casing and the stopper is provided at a top of the supporting member to accommodate the projection.
 17. The linear compressor according to claim 15, wherein the supporting member comprises: one or more combining parts coupled with the top of the vibrating member, radially extending downward from a center of the supporting member.
 18. The linear compressor according to claim 16, wherein the supporting member comprises: one or more combining parts coupled with the top of the vibrating member, radially extending downward from a center of the supporting member.
 19. The linear compressor according to claim 17, wherein the projection comprises: an opening formed therein along a vertical direction.
 20. The linear compressor according to claim 18, wherein the projection comprises: an opening formed therein along a vertical direction.
 21. The linear compressor according to claim 13, wherein the projection and the stopper have a common shape.
 22. The linear compressor according to claim 21, wherein the projection and the stopper have a cylindrical shape.
 23. The linear compressor according to claim 19, further comprising: a stationary shaft passing through the opening when engaging the movable unit and the vibrating member to facilitate an engagement operation.
 24. The linear compressor according to claim 20, further comprising: a stationary shaft passing through the opening when engaging the movable unit and the vibrating member to facilitate an engagement operation. 